JTAG & OCD Commander

The OCD Commander is macraigor's free debugger software, which allows you to connect to your supported target type chip via the On-Chip Debug port (BDM or JTAG) using a Macraigor hardware device. You will be able to test the connection, memory access, modify memory and registers, run code and more using this product. This debugger is not designed to be used to program flash devices connected to your target.
The OCD Commander software is supported under Windows 98/ME, NT, 2000, 2003, XP operating systems

supported devices

mpDemon

Raven

wiggle <------- it will be illustrated

usb2demon

usb2sprite

usbwiggler

See How To build the JTAG Wiggle interface & add the JTAG connector at J10, Just in case you make a brick, you could fix the jam, using this procedure: JTAG Bootloader Installation

JTAG add the J10 to the board

J10

To add the J10 to the board suck or wick the solder out of the holes and solder it in, but be minded a common header has pins larger than holes, so ... be careful about what you do: you could damage the PCB

About the software for the jtag cable

'cause in the new OCD-commander AMCC PowerPC PPC405 wiggler is NOT supported

'cause in the new OCD-commander IBM PowerPC PPC 405 wiggler is NOT supported

you need to download this old version, that i tested with success under windows2000
OCD-Commander-for-wiggle.zip (i can't include it for download cause of the copyright, if you need it, please email me)

parallel port setting

bidirectional

ecp

epp <---- set to this

OCD setting

target processor IBM, ppc4xx

interface driver wiggler

press reset, halt, cpu

you can understand everything is OK if PC=fffffffc (that is where PC points at boot)

NOTA
jtag scan is not pretty working, it needs to reset the TAP machine, but only OCD has been programmed to do that (i guess why ... anyway)

get started

OCD-commander packets is composed by

OCD-cmd

jtag-chain-scan

jtag-chain-scan does not reset the target board, so if you want to run it you need to invoke OCD-cmd and hardly force "reset", then you could use the jtag-chain-scan

OCD-* has been tested on

windows 2000: success, it is my reference working env

windows NT (it needs service pack6): a bit of issues ... not suggested

what about *nix ? maybe sooner or later you will be interested about implementing a jtag tap machine on microchip PIC (usb, ethernet, serial) and porting a ppv405gp bdl scan ? if so, let me know (see how to contact me)

JTAG build the Wiggle Cable

the the "Wiggler Buffered JTAG Programmer" is compatible with the old OCD. This schematic has been tested and it is working.

OCD, Recovering a bricked board (download and use the recovery kit)

Using OCD Commander, a JTAG adapter, and GPSFan's ram resident ppcboot, it is possible to reprogram the flash. In short, use OCD Commander to turn on the sdram, download the ram targeted ppcboot, and install a new bootloader.

It contains an OCD macro and an experimental ram-resident version of u-boot-1.1.4 that can be downloaded to 0x400000 (and executed at 0x400100). Expect to see much more output at boot, as this version has debug output turned on.

changes:

debug enabled

ram entry point in the linker script

output file u-boot.s19 and u-boot.elf

sdram config disabled

added debug info on code relocation

modified default environment

bug:

it doesn't work if you have more than 32Mb of ram

install:

Start OCD Commander, connect to the board, reset, and halt.

type "reset"

The CPU should be ready to fetch the first instruction:

type "cpu"

PC: FFFFFFFC CR: 00000000 MSR: 00000000 LR: 01FD327C

Configure the system:

recovery_config (Or hit the macro button and navigate to the recovery_config.mac file.)